This invention relates to a method and apparatus for treating hydrocarbon materials that are in the form of liquid or gaseous state which may also contain sulfur that needs to be removed in order for the materials to become benign from an environmental stand point, when consumed. These hydrocarbons may be derived from any of the following:-Heavy petroleum crude, tar sands, coal, oil shale, asphalt, syncrude, residium, oil refinery waste, and so forth. In the description of this patent application which follows the term “bitumen” shall be used exclusively to denote anyone or all of the above materials for the sake of simplifying the description of the invention.
The present invention encompasses improvements made to U.S. Pat. No. 5,356,530 issued to Albert Calderon. These improvements reside in structural modifications to better practice the method, in the manner of heating, in the movement of the solid catalyst, in desulfurization, in energy conservation and in the reduction of capital costs.
Briefly, the above mentioned reference comprises the charging of a petroleum material into a vessel having a cylindrical wall, then heating the wall indirectly. The petroleum material adjacent to the wall is heated to a temperature sufficient to crack hydrocarbons and form a layer of carbon against the wall, thus generating volatile matter which leaves the vessel, the carbon deposited next to the wall being periodically removed from the wall by scraping. The disadvantages of this reference are as follows:
The apparatus to carry out the method is cumbersome and complex, requiring large capital investment while at the same time making the process difficult to operate and to maintain. The material charged into the vessel upon heating becomes quite fluid and does not adhere to the wall of the vessel uniformly but runs down to the bottom of the vessel. Further, any carbon that is deposited against the wall forms an insulating barrier to the rest of the material within the vessel thus reducing the rate of heat transfer making the process inefficient. Great difficulty is experienced in the movement of the solid catalyst in gas cleanup system 23 (column 4, lines 46 & 47), in pyrolysis cylinder 24a (column 5 line 35) as well as in all other cylinders (vessels) by virtue of each vessel having a conical bottom for the discharging of the solid catalyst. Such conical shape often causes bridging of the catalyst within the vessel, which interrupts the flow of the catalyst thus causing forced shut-downs.